Gubernaculum as icebreaker: do matrix metalloproteinases in rodent gubernaculum and inguinal fat pad permit testicular descent?

J.A. Churchill, S. Buraundi, P.J. Farmer, R.L. Li, B.R. Southwell, J.M. Hutson, A. Balic

Research output: Contribution to journalArticlepeer-review

Abstract

Purpose: Cryptorchidism is the most common male congenital abnormality. The rodent gubernaculum steers the testis from abdomen to scrotum postnatally by eversion and migration through the developing inguinal fat pad (IFP). We hypothesize that extracellular matrix remodeling in/around the gubernaculum is necessary for eversion and migration and is permitted by timed IFP maturation and aimed to examine regional development and matrix metalloproteinase (MMP) content. Methods: Embryonic day 19 (E19) and postnatal days 0 and 2 (P0, P2) wild-type Sprague-Dawley rats (n = 10) were prepared for histologic examination (trichrome) and immunohistochemistry (membrane-type MMP-1 [MT1-MMP], MMP2) and analyzed using light/confocal microscopy. Results: At E19, IFP contained fibroblasts and immature cells in an extensive collagenous extracellular matrix. Cells in the gubernaculum base were cytoplasmic-MT1-MMP-positive (inactive). At P0, the gubernaculum had everted, and adjacent cells were membranous-MT1-MMP-positive (active). At P2, the gubernaculum was migrating through the IFP, and adjacent cells were membranous-MT1-MMP-positive. Adipocyte maturation began cranially in the IFP and proceeded in a craniocaudal gradient until more uniformly mature at P2. Conclusion: The MT1-MMP-positive cells may remodel the gubernaculum for eversion and provide the collagenolysis necessary for migration, like an icebreaking ship, through the IFP, which matures to permit migration through collagen-rich tissue. Disruption of these processes may cause cryptorchidism. (C) 2011 Elsevier Inc. All rights reserved.
Original languageUndefined/Unknown
Pages (from-to)2353-2357
Number of pages5
JournalJournal of Pediatric Surgery
Volume46
Issue number12
DOIs
Publication statusPublished - 2011
Event44th Annual Meeting of the Pacific Association of Pediatric Surgeons - Cancun, Mexico
Duration: 10 Apr 201114 Apr 2011

Keywords

  • Testicular descent Cryptorchidism Gubernaculum Inguinal fat pad Matrix metalloproteinase MT1-MMP mammary tissue link rat

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